Patent GB-1001213-A (GB)
Title: Preparation of phenolic phosphonates
IPC: C08K5/5333
Filed: 1964-02-24
Abstract: Compounds of the general formula: <FORM:1001213/C2/1> wherein Ar is an alkyl-substituted hydroxyphenyl radical having at least one alkyl group ortho to the hydroxy group on the phenyl nucleus, said alkyl having up to 18 carbon atoms, X is an alkylene group having 1 to 6 carbon atoms, and R0 and R1 are each independently alkoxy having 1 to 24 carbon atoms, phenoxy or alkylphenoxy having 7 to 24 carbon atoms, are obtained by reacting a compound having the formula <FORM:1001213/C2/2> wherein Ar and X are defined as above, with a compound of the formula <FORM:1001213/C2/3> wherein the R groups are independently alkoxy having 1 to 24 carbon atoms, phenoxy or alkyl phenoxy having 7 to 24 carbon atoms. In a modification compounds of Formula I obtained as above, in which R0 and R1 are aromatic radicals, may be further reacted with an aliphatic alcohol having 1 to 24 carbon atoms, or an alkyl phenol having 7 to 24 carbon atoms. The substituted phosphite of Formula III and the arylalkanol of Formula II are preferably used in substantially equimolar quantities, although either may be present in considerable excess of the molar quantity of the other.  The process may be carried out in the presence of a solvent and suitable solvents include aromatic hydrocarbons having 6 to 12 carbon atoms, saturated hydrocarbons having 5 to 19 carbon atoms, aliphatic carboxylic alkyl esters, glycol diethers, single ethers or nonreactive solvents generally. Neutral phosphate esters are also useful. The reaction temperature may vary from 20 DEG  to about 300 DEG  C. preferably within the range 100 DEG  to 250 DEG  C. Catalysts may be present, e.g. alkali metal halides, alkyl halides, halogens, and Lewis acid halides.  In the subsequent transesterification reaction alkali metal phenoxides, alkali metal alkoxides or alkali metal borates may be used as catalysts.  This reaction will proceed in the absence of solvents or in the presence of inert solvents such as those hereinbefore mentioned. Examples are given for the preparation of dimethyl, di-n-octadecyl-, di-(p-t-octylphenyl)-and diphenyl - 3,5 - di - t - butyl - 4 - hydroxybenzyl phosphonates, di-p-tolyl-2-hydroxy-3-t-octyl - 5 - methylbenzylphosphonate, di - (p-octadecylphenyl) - 3 - t - butyl - 4 - hydroxy - 5-n-octadecylbenzylphosphonate, di - n - docosyl-1 - (3 - t - butyl - 4 - hydroxy - 5 - methylphenyl) - ethane - phosphonate and di - n-dodecyl - 1 - (3 - t - butyl - 4 - hydroxy - 5-methylphenyl) - n - hexanephosphonate; and for the transesterification of diphenyl-3,5-di-t-butyl - 4 - hydroxybenzylphosphonate with n - octadecanol or p - t - octylphenol to give di - n - octadecyl - 3,5 - di - t - butyl - 4-hydroxybenzylphosphonate or diphenyl - 3,5-di - t - butyl - 4 - hydroxybenzylphosphonate respectively and di - t - butyl - 4 - hydroxybenzylphosphonate with n-octanol to give di-n-octyl - 3,5 - di - t - butyl - 4 - hydroxybenzylphosphonate. The products are useful as anti-oxidants for gasoline, kerosine, and other hydrocarbon fuels, hydrocarbon and oxygenated solvents, lubricating and other industrial oils, petroleum wax, rubber and rubber - like materials, liquid olefinic material and solid polyolefine materials.  Compounds of Formula II may be prepared by reaction of the ortho substituted phenol with an aldehyde such as formaldehyde, or by hydrolysis of the corresponding aryl-substituted alkyl halide, which may be prepared from the appropriate alkyl phenol, formaldehyde and hydrogen halide.  Compounds of Formula III may be prepared by reaction of a suitable alcohol with phosphorus trichloride in the presence of base, e.g. pyridine.  Reference has been directed by the Comptroller to Specification 948,880.